In the scope of this invention, “functional unit” and other similar expressions are used to indicate a clearly predefined sequence of sequential operations executed automatically and linked to one another; in short, these expressions are used to indicate a macro instruction composed of several minor instructions linked to one another from a standpoint of time and function.
Furthermore, in the scope of this invention, the term “bottling” in reference to a heat recovery steam generator is used to indicate the total of a series of activities designed to isolate the same steam generator and the peak heating cycle from the external environment and other components of the system as much as possible, in order to retain all of the accumulated heat within the generator as long as possible. The bottling operation is executed by implementing opportune actions on the system's insulation systems (valves, dampers, etc.).
The electric power production systems described above, also noted as combined cycle systems in relation to the fact that these systems require a recovered heat steam cycle subordinate to a preliminary cycle to generate electric power through the implementation of one or more gas turbine and generator units, are quite common at present due to their extreme flexibility of use which allows variations in the quantity of produced power within an extended range of percentages in reasonable time limits, while maintaining good overall yield when the system reaches the fully operational phase.
Moreover, the combined cycle heating system for the production of electric power can also be stopped and restarted within reduced time intervals.
For combined cycle heating systems for the production of electric power, the transitory phase, which comprises the stages in which the system changes functioning modes, is very critical. Examples of possible transitory stages in the functioning of the system are as follows:                during the startup phase from a stopped system through startup of a single gas turbine and generator unit and subsequent ground running and loading of the steam turbine (TV);        during the startup phase of the second gas turbine and generator unit with the first gas turbine and generator unit already running, as well as the steam turbine;        during the complete stopping of the system starting from an initial condition in which only one gas turbine and generator unit is operating or        during the stopping of a gas turbine and generator unit from an initial condition in which two gas turbine and generator units are operating.        
It is almost superfluous to explain how the aforementioned transitory stages of system operations are critical from the following points of view:                1) from the structural stress that the various system components are subjected to (for example, due to the heavy-duty operating conditions or the temperature fluctuations in the range of several hundreds of degrees absorbed within only a few hours) and        2) the decisional randomness and discretionality left to the operator when startup is carried out as a sequence of manual operations as opposed to automated operations        
In addition, the transitory stages are penalized from the standpoint of comprehensive efficiency of the system, in particular as pertains to the startup phases.
Furthermore, it is also evident that during the transitory stages of the system startup from an initial condition with the system completely stopped there is an increase in polluting atmospheric emissions.
As described above, it is evidently necessary to operate the system through startup sequences and stopping procedures which:                are as optimized as possible, in order to reduce the mechanical and thermal stress on the components,        allow reduction to a minimum of the duration of the transitory stages without excessively penalizing the comprehensive yield of the system and        allow reduction to a minimum of potential errors, limiting the discretional component of the operator as much as possible.        
Since for each system component, such as, for example, the gas turbine and generator unit, the steam generator or the steam turbine must follow a specific functional unit, and it should be noted that a clearly determined sequence of subsequent operations, from startup to stopping, provided by the manufacturer of the same component in order to address the aforementioned requirement, creates the problem of how to correctly link the functional units of the various components of the system to obtain a harmonious startup and stopping procedure that takes the system from an initial condition of, for example, a stopped system, to a secondary condition of, for example, a running system.
Currently, the aforementioned harmonious procedure for executing the correct sequence of functional units is the responsibility of the plant technicians, who start from a written sequence of the functional units specifically arranged for the system and follow the procedure. In this regard, it is appropriate to highlight the fact that even though this is correct from a chaining standpoint, the sequence of the functional units is executed according to timing on a case-by-case basis established by the plant technician, who based on personal gained experience evaluates the specific physical and functional parameters of the system, and decides based on personal experience which operations to carry out for commissioning the various components required for startup.
This procedural method is not satisfactory because it constantly requires the presence of plant technicians who have acquired long-term experience with the specific plant to start/stop the equipment, which inevitably leads to conflict due to the fact that different technicians will implement different startup times, and even though they may be correct, this does not permit constant optimization of the procedure while at the same time satisfying this requirement.